Water circulator



' N v- 2 9- E. s. CORNELLJR WATER CIRQULATOR 2 Sheets-Sheet 1 .Filed Aug. 4, 1937 INVENTOR 1 DW D syNELzJR. NEY

NOV. 21, 1939. s, EL JR 2,180,401

WATER CIRCULATOR File'dAug. 4,- 1957 2 Shets-Sheet 2 INVENTOR E ARD s.coR LL,JR.

TORNEY Patented Nov. 21, 1939 a Edward S. Cornell, Jr., Larchmont, N. Y., assigna or, by m'esne assignments, to American Radiator & Standard Sanitary Corporation, New York, N. Y., a corporation of Delaware Application August 4, 1937, Serial No. 157,272

3 Claims.

This invention relates to centrifugal pumps. The invention is directed to improvements in centrifugal pumps, and has for its object, broadly, an improved pump particularly suitable for serv- 5 ice in heating systems employing circulation of hot water or other heat-containing liquid through a closed'piping system incorporating a heat generator or boiler" and one or more radiators.

More specifically, objects of the invention inelude: provision of an improved pump casing, l arranged to impart an initially rotative direction to, the inflowing liquid prior to its passage through the eye of the impeller, thus bringing the liquid into contact with impeller substantially without shock, eliminating noise-producing vibrations, and increasing emciency; provision for an ample reservoir above the impeller, to quiet turbulences in the incoming liquid prior to its introduction to the impeller; provision for the location of inlet and discharge ports at one side of the pump casing, to compact the pump and thus facilitate its location within the boiler housing or jacket;

and provision for a vibration-dampening mountranged for horizontal'mounting, with inlet and outlet passages forming'the branches of the U, and thereby being adjacent; a source of motive power resiliently mounted on the said casing; and a centrifugal impeller arranged for rotation within a race at the base of the U'.

It is a feature of the invention that the impeller race is eccentrically located within the casing, that is, is located in the general direction of the discharge passage. Such location of the impeller race imparts definite advantages, namethe inlet side, as compared with the volume at the discharge side, such enlarged capacity acting to reduce turbulencesin the inflowingv liquids; and the provision of an improved organization 45 of elements at the inlet side, for imparting to the infiowing stream a gradual change in its direction of flow and'a concomitant increase in the velocity of the lnflowing stream at ,its introduction to the impeller. The stream is thereby 50 brought into contact with the impeller in a direction substantiallytangential to the circleofrotation of the impeller, and at increased velocity, thus minimizing vibration and wear-causing shock which ordinarily results in centrifugal 55 pumps from a sudden change in direction and/or ly, the provision of a relatively large capacity at velocity in the inflowing stream as it approaches the impeller.

Yet another feature is that the initialrotative direction imparted to the stream by the inlet configuration cooperates advantageously with the 5 backward-discharge angle of the impeller blades,

- said blades cutting into the stream at an acute angle, and thus without creating excessive vibrations or turbulences in the discharging stream.

Other features and advantages hereafter apl0 pear. I

In the accompanying drawings: Figure 1 is' an elevation of the assembled pum showing the relative location of the inlet and discharge ports; 15

Figure 2 is a horizontal section taken through 2-2 of Figure 1 showing the pump casing, impeller and impeller race;

Figure 3 is a partial vertical section showing details of the impeller and its mounting; and 20 Figure 4 is a vertical section taken through 4-4 of Figure 2 showing the configuration of the pump casing and the relative location of the im- 'peller race.

' Referring to the drawings, a centrifugal pump It includes driving means ii resiliently mounted on a pump casing 12 by an intermediate spider iii. The casing I2 is preferably a casting, and generally U-shaped, see Fig. 2, with inlet and discharge passages l8 and 55 respectively, forming the branches of the U. At the rear of the casing l2, and eccentrically located to be in the zone of the discharge passage it, there is provided an impeller race it adapted to receive a rotary impeller i1 connected by a shaft l8 and suitable flexiblecoupling I!) to driver H. Re silient means, such as aspring suspension or the rubber sleeves 20 and washers 20a, see Fig. 3, effect a vibrationand sound-absorbing connection between the motor i l the spider it, and the pump-casing bonnet or cover 2i. Bolts 22 effect, a demountable assembly. v

The bonnet or cover 2! may be removably secured to the pump casing l2 bysuitable bolts 23 and fluid-tight gasket 24. Shaft I8 is introduced into the casing I2 through a fluidand pressuretight gland comprising a threaded packing nut 25 having depending walls 25a enclosing suitable packing material 26. The lower surfaces of the wall 250 bear against packing rings 26a, which may thereby be compressed between a washer 26b and the lower surfacerof wall 25a, about the shaft IB. I prefer to employ a main shaft bearing 21 of the oilless type, removably housedwithin a neck 28 depending from, and preferably integral with, the bonnet 2|. Bearing 21 may be lubricated by a wick 21a suitably-confined'between neck 28 and bearing 21, and fed through channel 32 by grease cup 32a. Shaft l8 may be supported on a' stainless steel ball 29 housed within a suitable recess 30 .in casing i2, and carried on a bearing block 3|, also preferably of stainless steel or other'suitable wearand corrosion-resisting material. Accurately aligned cooperating spherical depressions in block 3! and shaft l8 impart to the ball 29 the combined functions of thrust bearing and shaft alignment means. Unequal wear occasioned by improper shaft. align-. ment or balance of impeller l1- is avoided. A washer 28a may be interposed between bearing 28 and the base of impeller l'l.

The pump may rest upon a shock absorbing base, such as the rubber ring 33, keyed into arecess 34 at the base of the pump casing l2. Flanges 35, 36 may be used at the inlet and outlet discharge ports to facilitate piping connections; pipes 351%, 36a are shown in Figure 2.

In Fig. 1 there is illustrated a reaction stop, comprising a tongue Ila, formed preferably as an integral part of the motor housing, and a cooperating rubber-clad bumper [3a carried by the spider to limit the reactionary axial rotation of the entire motor casing with respect to the spider as the pump starts.

The impeller H, see Figs. 2 and 3. is illustrated as having a plurality of backward-discharge- As indicated in Figs. 2 and 3, the blades 48 are substantially tangential to the circle defin ing the outer wall of the aforementionedbearing neck 28, although obviously clearably spaced therefrom to permit free rotation of the blades about the stationary neck. The blades may be of full width for approximately one-half of the height, at which point they may be stepped, as shown in Fig. 3, to conform to the width of the annulus 42 and thus form passages or ports 44 directed to the allowance of convection-induced flow of water through the impeller and to the outlet IS in an inoperative period of the circulator.

The impeller race is is defined by an integral wall formed in part by the wall of pump casingsee Fig. 2, in which a portion of the pumpcasing wall at the discharge side has been broken away to clear the discharge port l5a of the impeller race-and in part by an upstanding wall 58. see Figs. 2 and 4, which may conform in height to the top of the impeller annulus 42. At

the inlet side, the wall may include a tongue or barrier 52, as shown in Fig. 2, which, in cooporation with the surface of the wall 50,.the rear the said reservoir advantageously having a volume substantially equal to that of the impeller race I6, with which the saidreservoir is con- I nected by the impeller eye 43.

It is a feature of the invention that, as clearly shown in Fig. 2, the eccentric location of the impeller race within the pump casing imparts to both the inlet and discharge passages, at the impeller, a configuration which is of the nature of a volute. and that the relatively constricted inlet i4a moderately increases the velocity of the stream as it enters the reservoir 53 to minimize the sudden change in the velocity of the inflow- 5 ing stream which is frequently a source of shock in centrifugal, pumps.

An additional feature lies in the cooperation of the rear wall of the impeller casing and the tongue 52,'see Figs. 2 and 4, to impart an inil0 tial rotation to the inflowing liquid stream, causing it to enter the reservoir 53 in a direction substantially tangential to the circle of rotationof the impeller and thus to pass through the eye 43 to be acted upon by the impeller blades 16 without undergoing a sudden change in direction. It is evident also that by imparting such rotation to the inflowlng' stream, the basic advantage of the backward discharge slope of the blades of the impeller is accentuated, as the 20 blades and stream travel in substantially the same direction and the blades are not caused to slap their way into the stream against a conflicting direction of flow.

Provision is made for the elimination of short 26 circuiting losses, that is, losses occasioned by the escape of liquid from the impeller race i6 to the reservoir 53, at A, Fig. 3, by providing the impeller annulus 42 with an outwardly projecting flange 54, which is arranged to overlie a horizontal shelf 55 formed in the impeller race defining wall, as shown in Fig. 3.

It will thus be seen that features of the invention have been directed to the elimination of hydraulic shocks, which normally in centrifugal 35 pumps are caused by a sudden change in the direction of the flow of liquid, asudden change in the velocity thereof and/or a sudden reduction in the clear passage area between the inlet port and the impeller. Sudden shocks, occurring in apump employed in a closed heating system, would engender noise-inducing vibrations which would be a source of annoyance at every portion of the heating system. v

Additionali'details directed primarily to ease of disassembling and servicing the circulator may be found by reference to Figs. land 3. In the latter figure, the impeller H, which may preferflanges are concave, to permit the distance on centers between inlet and outlet connections to be reduced to less than twice the flange radius. Each flange may thus be turned independently of the other, and without conflict therewith.

Such construction makes it possible to employ the flanges in lieu of union joints.

The circulator may be suspended from, or supported by the piping to which it is attached. Preferably, however, provision will be made for independently supporting the circulator, on the 7 annular rubber ring 32, which thereby serves as a vibration dampening base.

Whereas I have described my invention by reference to specific forms thereof, it will be understood that many changes and modifications 15 may be made without departing from the spirit of the invention.

I claim:

1. A centrifugal pump. includinga pump casing having inlet and outlet es tangentially located with respect thereto, an impeller race eccentrically located within said casing in the zone of the outlet passage thereof. a multi-bladed an increased velocity and in a direction sub-.

stantialiy tangential to the direction of rotation of said impeller, said passage means including a wall common tosaid chamber and to said impeller race and having a discharge orifice of smaller area than the sectional. area' of said inlet passage, communicating with the said chamber,

2. A centrifugal pump, including a substantially U-shaped pump casinghaving inlet and outlet es tangentially located with respect thereto, said inlet and outlet passages arranged I in a common plane and having openings defined by a common wall, a horizontally disposed impeller race eccentrically located within said weing in the zone of the outlet passage thereof, a multi-bladed impeller arranged to be rotated within said impeller race, a concave annular plate integral with said impeller blades and defining the upper edges of said blades, said annular plate arranged for rotation substantially entirely within said impeller race and in close proximity to a wall thereof, said annular plate having further, a flange at an upper edge arranged to overlie an upper surface oi said impeller race in close proximity thereto, the annular opening of said plate communicating with said impeller race, a

chamber having a volume substantially equal to' said impeller race disposed above said impeller nular plate, and passage means associated with said inlet passage arranged to direct in flowing fluid upwardly and to discharge said fluid into said chamber at an increased velocity and in a direction substantially tangential to the direction of rotation of said impeller, said passage means including a wall common to said chamber and to saidimpeller race and having a dischargeorifice of smaller area than the sectional area of said inlet passage, communicating with said chamber.

3. A centrifugal pump, including a substantially u-shaped pump casing having inlet. and outlet passages tangentially disposed with respect thereto, said inlet and outlet passages arranged in a common plane and having openings defined by a common wall, a horizontally arranged impeller race eccentrically located within said casing in the zone of the outlet passage thereof, said impeller race being wholly within a space defined by ,top and bottom surfaces of said inlet and outlet passages and having a base lying substantially in the plane of the lowermost portions of said inlet and outlet passages, a. horizon-l tally disposed multi-biaded impeller arranged to be rotated within said race, said impeller including an annular plat' supported upon the blades thereof, said plate having a central open ing communicating with said impeller race, a chamber having a volume substantially eqllll to the impeller race disposeda ve said impeller race, a floor of said chamber being formed'by said impeller-supported annulus, and passage, means associated with said inlet passage arranged to direct infiowing fluid upwardly and to 36 discharge said fluid into said chamber at an increased velocity and in a direction substantially tangential to the direction of rotation of said impeller, said passage means including a wall common ,to' said chamber and impeller race and having a discharge orifice of smaller area than the sectional area of said inlet passage .communicating with said chamber. 1

EDWARD S. CORNEIL, Jl. 46 

